Within the scope of minimally-invasive surgery, such as endoscopic or laparoscopic surgery, access to the operating site is made via small incisions in the body of the patient (such as the abdomen or thorax), in which the practitioner places a cannula formed by a tube whereof the diameter typically varies from 3 to 15 mm, through which the practitioner can insert into the body of the patient either an endoscope for obtaining a video image on a monitor, or long and fine instruments for performing a procedure at the operating site.
In some cases or for some specific intervention devices, access is made through a natural orifice, e.g. vagina when the intervention device is a uterine manipulator. Indeed a uterine manipulator is a device inserted in the uterus through the vagina and cervix to position the patient uterus without making a specific incision in the patient skin.
Manipulation of an intervention device through small incisions or through a natural orifice requires in both cases to move it around a fixed point or center of motion, which corresponds to the incision or natural orifice itself. Such incision or natural orifice is herein generally referred as a point of penetration in the patient.
Since the surgeon generally has both hands occupied by the surgical instruments, an assistant is necessary to maintain any other intervention device in a desired position, in particular the endoscope that is used to guide the surgeon in his surgery.
Robotic systems have been developed to handle and displace the endoscope in the place of the assistant. Such systems are generally formed of massive, complex, and expensive robots comprising a base attached to the ground and an arm handling the endoscope. In the limited space of an operation room, the base of such a robot takes up a considerable space close to the patient. Further, the arm of the robot maintaining the endoscope may hinder the access to the patient's abdomen.
Alternative solutions have thus been proposed consisting in holders designed to hold and move an intervention device, e.g. an endoscope, during surgeries. Such systems are much more compact and easy to use for the surgeon.
An example of such system is for instance described in U.S. Pat. No. 8,591,397 published on Nov. 26, 2013 that discloses a compact motorized endoscope holder placed directly on the patient's abdomen. More precisely, the motorized endoscope holder is formed of a base attached to a passive arm, a ring portion rotatably assembled on the base according to an axis perpendicular to said base, a longitudinal portion rotatably assembled on the ring portion according to an axis perpendicular to and intersecting the first axis, and a holding portion slidably assembled on the second portion along a translation axis intersecting the first two rotation axes at the same point. It further comprises electrical motors for actuating the ring portion with respect to the base, the longitudinal portion with respect to the ring portion and holding portion with respect to the longitudinal portion respectively. With such architecture, whatever the robot positioning, each electrical motor of the system activate a movement, which corresponds to a right/left, up/down or in/out movements of the endoscope respectively. The right/left and up/down movements are the two rotations enabling the viewing of the entire abdominal cavity, whereas the in/out movement is a translation displacing the endoscope closer to or further from the organs of interest.
Any order given by the surgeon, for instance by voice or foot, directly actuates one motor which moves the endoscope according to the required movement. One advantage of such a system is that it does not require any computer calculation for moving the endoscope. The system is thus very simple to use and configure but this also create artifacts in the movement depending on the current position of the endoscope. When moving a camera, right/left movement for the user corresponds to moving the camera field on the right or left side of the field of view in a direction perpendicular to the up/down direction of the image. Due to the arrangement of the elements of the system, orientation of endoscope axis with respect to right/left movement axis is modified by up/down movement. When the rotation axis is not perpendicular to the longitudinal axis of the endoscope, then the movement due to the rotation around such rotation axis is not linear on the image but rather makes an arc which creates the above mentioned artifacts in the visualisation given to the surgeon.
A goal of the present invention is to propose a simple and easy to use system for controlling displacement of an intervention device, in particular an endoscope, that addresses the above mentioned drawbacks.
In particular, a goal of the present invention is to propose a simple and easy to use system for controlling displacement of an intervention device, in particular an endoscope, that gives accurate information to the surgeon during his surgery.